Composite yarn and process therefor



Aug. 22, 1967, P. FA MARSHALL 3,336,743

` COMPOSITE YARN'AND PROCESS THEREFOH Filed Deo. 6, 1965 United StatesPatent Ofiice 3,336,743 Patented Aug. 22, 1967 Filed Dec. 6, 1965, Ser.No. 511,625 6 Claims. (Cl. 57-144) This invention relates to a compositeyarn comprising a plurality of vstrands held together without subjectingthem to a cementing or twisting operation. More particularly it relatesto a process whereby lamentary loops deriving from the fbody of one ofthe strands are wrapped around said strand and around at least one otherstrand, thereby binding the strands together.

Plied yarns are conventionally made by bringing together two or morestrands and combining them by a twisting operation. Mechanicallimitations on the speed of twisting devices has made this an expensiveoperation in comparison with most yarn-processing operations.Additionally, when soft or bulky yarns are being plied, there is aninevitable loss in softness and loft in conventional twistingoperations.

It is therefore an object of this invention to provide a composite yarnin which two or more strands are held together without being twisted onearound the other.

It is also an object of this invention to provide a composite yarnwherein lamentary loops deriving from at least one lamentary strand arewrapped around said strand and around at least one other strand, wherebySaid strands are held in juxtaposition.

The invention Will be more clearly understood from the followingdescription and drawings, in which:

FIGURE 1 represents a wrapped yarn useful in the process of thisinvention.

FIGURE 2 represents, in simplified form, the yarn of FIGURE 1 combinedwith a second strand, according to this invention.

FIGURE 3 represents two yarns both similar to the yarn of FIGURE l,combined with each other according to this invention.

FIGURE 4 represents, in cross-section, an apparatus suitable forproducing the yarns of this invention.

In general, the process comprises:

(l) Forming a wrapped yarn comprising at least one core strand, with atleast one wrapping strand -disposed around the core strand in the formof doubled-back loops, the loops overlapping the core for a plurality ofturns, and the wrapping strand possessing no net true twist around thecore strand. The process for making such a wrapped yarn is set forth inmy U.S. Patent 3,041,812, wherein the looped wrappings are explained asin part extending radially from the yarn axis.

(2) Passing at least one such wrapped yarn, together with at least oneadditional strand of similar or different nature, through the apparatusof FIGURE 4 while subjecting both yarn and strand to the action of awhirling cylindrical body of fluid introduced into the apparatus ofFIGURE 4, whereby the loops extending radially from the body of thewrapped yarn are further wrapped about the yarn and strand to form acomposite yarn.

Referring to FIGURE 1, a wrapping strand 12 is shown as disposed in theform of doubled-back loops 13 around a core strand to form a wrappedyarn 14. Such yarns are described, for example, in U.S. Patent3,076,307. The core strand may be a multiiilament strand, or amonoilament such as a wire, its chief functions being as a scaifoldaround which to dispose the looped wrapping strand and as a load-bearingmember in the final structure.

The wrapping strand in the yarn of FIGURE l is preferably a continuousmultilament strand, and may be of viscose, acetate, nylon, or othermultifilamentary material as desired. Apparatus suitable for conductinga wrapping process of this nature is set forth in U.S. Patents 3,082,591and 3,041,812.

FIGURE 4 represents the combining of the wrapped yarn 14 of FIGURE 1with another strand 16, of any desired nature, in an apparatus which isthe same as the apparatus used to form yarn 14. As shown, it comprises acylindrical vortex tube 18 consisting of walls 20, entrance and exitopenings 22 and 24, air inlets 28, and an axiallydisposeddownwardly-extending control tube 26. This apparatus is illustrated andfully described in said U.S. Patent 3,082,591, an-d reference is herebymade thereto for an understanding of the various components and theirfunction.

The wrapped yarn 14 and the second strand 16 are supplied to the vortextube 18 from conventional packages, not shown, their feed rates beinggoverned by letoif rolls, star wheels, or other conventionalspeed-governing mechanisms, also not shown. As air under pressure's fedinto the vortex tube 18 through either of the air inlets 28, a whirlingcylindrical body of air is established inside the tube, as shown. Thiscauses a .sort of crankshaft motion in the wrapped yarn and the secondstrand, tending to draw them together with a twisting motion upstream ofthe center of the tube, as at 30'. At this point the two strands appearto be plied. This is a false twist or false plying, however, and thetwist imparted upstream nal product one strand may in places appear tobe wrapped around the other with several turns of true twist, in theprocess of this invention there is no true relative motion of strand 16around the wrapped yarn 14: hence there can be no true net twist of onestrand around the other, and if a section of the product appears toexhibit a true ply, another section will be found to exhibit an equalnumber of ply turns in the opposite direction.

In FIGURE 2, the composite false-plied yarn 32 is shown as consistingofthe strand 16 bound to the wrapped yarn 14 of FIGURE 1 by the processjust set forth. The wrapping strand 12 of the wrapped yarn 14 is nowunited to the second strand 16 by means of doubled-back loops ofwrapping strand, as at 15. This is a second wrapping operation, in thesense that the wrapping 15 derives from the elongated loops 13 presentin the original Wrapped yarn 14 of FIGURE 1.

In FIGURE 3 there is shown the result of passing two wrapped yarns, eachof the nature of FIGURE l, through the apparatus of FIGURE 4. The upperyarn consists of a core strand 10 with a wrapping strand 12 disposedaround it in looped form, as previously described. The essentiallysimilar lower yarn 16 consists of a core strand 11 with Wrapping strand17 similarly disposed. After passing both yarns through the process ofFIGURE 4, the two yarns will be mutually bound together by wrappings 15`derived from the elongated and radially-extending loops of the upperyarn and by similar wrappings 19 derived from similar loops originallypresent in the lower yarn.

Although the various wrappings shown in FIGURE 2 and 3 are represented,for the sake of clarity, as being like a doubled loop of a singleWrapping strand, when a low-twist multifilamentary strand is used forwrapping, the process illustrated in FIGURE 4 will to at least someextent separate sorne of the filaments of the wrapping strand intosmaller groups of filaments, so that the nal yarn has a very soft, fuzzyand appealing hand. By using wrapping strands and core strands ofdifferent colors, a variety of interesting heather and speckled effectscan be realized, in which the colors alternate in a haphazard and randomfashion. Textured effects can be produced from the combination of awrapped yarn of FIGURE 1 with a slub or nub yarn as the second strand,such slubbed strands being I 3 described, for example, in U.S. patentapplication Ser. No. 374,743, tiled June 12, 1964, now U.S. Patent No.3,280,- 546.

Previous attempts to develop a plied yarn effect without carrying out aplying operation have included processes such as described in U.S.Patent 2,895,285, to Hilbert, wherein larnentary loops are formed on thesurfaces of multifilament yarns and the loops of one yarn are entangledwith the loops of the other yarn. Such a surface engagement, however,does not develop as strong a yarnto-yarn union as the wrapping processin the yarns of the present invention, which are remarkable in theirability to withstand such processes as coning and knitting withoutseparation.

The process of the invention will be illustrated by the followingexamples.

Example 1 Using the apparatus of FIGURE 4, two wrapped yarns similar tothe yarns of FIGURE 1 were prepared by the general procedure describedin U.S. Patent 3,082,591. Each wrapped yarn consisted of a nylonwrapping strand, 70 denier 34 filament, on a 140 denier 68 filamentnylon core. The cores were white in both cases, while one wrappingstrand was white and one black. Approximately 6.9 yards of wrappingstrand in each case was disposed around one yard of core strand in theform of doubled-back loops which at intervals extended radially at adistance from the core strand as at 13. The control tube 26 extendeddownwardly into the vortex chamber 18 so that its lower end was aboutparallel with the air inlets 28.

For combining these two wrapped yarns to give the product of FIGURE 3,the control tube 26 of FIGURE 4 was adjusted upward until it was flushwith the upper inside wall of the chamber. The control tube 26 seems tohave an effect on the configuration and power of the whirling mass ofair within the vortex tube, and its Withdrawal seems to promote thewrapping of the loops of each strand (13 of FIGURE 1) around bothstrands when they are brought together in the chamber.

The two strands, 14 and 16 of FIGURE 4, were fed to the vortex chamberat a rate of 350 feet per minute, with a 90 p.s.i.g. air pressuredelivered to one of the air-inlets 28. The result was a falsely-pliedyarn, represented by FIGURE 3.

Example 2 A nubbed yarn was produced according to Example 1 of U.S.Patent application Ser. No. 374,743, filed June 12, 1964, now U.S.Patent No. 3,280,546, using the apparatus described therein. Then, usingthe combining or false plying operation set forth in Example 1, is Waspassed together with a wrapped yarn of the type set for-th in Example 1through the apparatus of FIGURE 4 under the conditions set forth inExample 1.

The result was a textured and falsely-plied yarn with a nubbed effect atirregular intervals, the two yarns being held together by filamentaryloops from each yarn being wrapped at intervals around both yarns.

Having thus described my invention, I claim:

1. A composite yarn comprising a wrapped yarn formed from at least onewrapping strand and at least one core strand,

said wrapping strand being associated with said core strand in the formof doubled-back loops wound around said core strand for a multiplicityof turns,

together with a falsely-plied strand secured to said wrapped yarn atperiodic intervals by a secondary wrapping,

said secondary wrapping comprising loops derived from the wrappingstrand of the wrapped yarn being disposed around said falsely-pliedstrand and around said Wrapped strand,

said wrapped strand and said falsely-plied strand possessing no net truetwist around one another.

2. The product according to claim 1 in which the falsely-plied strand isa textured yarn characterized by alternating thick and thin areas.

3. A composite yarn formed from at least two wrapped yarns,

each wrapped yarn comprising a core strand and a wrapping strandassociated therewith,

the wrapping strand in both yarns being disposed around its core strandin the form of doubled-back loops wound for a multiplicity of turnsaround said core strand,

each wrapping strand at periodic intervals also being disposed aroundboth elements of the composite yarn in the form of doubled-back loopswound about both elements for a multiplicity of turns,

the two wrapped yarns forming the composite yarn possessing no net truetwist around one another.

4. The method of producing a falsely-plied yarn which comprises passingat least one wrapping strand and at least one core strand through agenerally cylindrical body of uid whirling about a central axis,

the wrapping strand being fed at a rate faster than the core strand,

disposing the wrapping strand around the core strand in the form ofdoubled-back loops wound for a multiplicity of turns around said corestrand,

a portion of said loops at intervals extending radially outward from theaxis of said core strand;

bringing the thus-formed wrapped yarn into justaposition with a secondstrand,

passing the combined yarn and second strand through a generallycylindrical body of fluid whirling about a central axis,

wrapping at least some of the radially-disposed loops of the wrappedyarn around both the second strand and around the wrapped yarn,

and removing the thus-formed falsely-plied yarn from the whirling bodyof fluid.

5. The process according to claim 4 wherein the second strand is anotherwrapped yarn and the radially-extending loops of each yarn are wrappedabout both yarns.

6. The process according to claim 4 wherein the second strand is atextured yarn possessing alternating -thick and thin areas.

References Cited UNITED STATES PATENTS 3,041,812 7/1962 Marshall 57-63,078,653 2/1963 Marshall 57-144 X 3,082,591 3/1963 Marshall 57-63,280,546 10/1966 Spicer et al 57-144 FRANK I. COHEN, Primary Examiner.

I. PETRAKES, Assistant Examiner'.

1. A COMPOSITE YARN COMPRISING A WRAPPED YARN FORMED FROM AT LEAST ONEWRAPPING STRAND AND AT LEAST ONE CORE STRAND, SAID WRAPPING STRAND BEINGASSOCIATED WITH SAID CORE STRAND IN THE FORM OF DOUBLED-BACK LOOPS WOUNDAROUND SAID CORE STRAND FOR A MULTIPLICITY OF TURNS, TOGETHER WITH AFALSELY-PLIED STRAND SECURED TO SAID WRAPPED YRAN AT PERIODIC INTERVALSBY A SECONDARY WRAPPING, SAID SECONDARY WRAPPING COMPRISING LOOPSDERIVED FROM THE WRAPPING STRAND OF THE WRAPPED YARN BEING DISPOSEDAROUND SAID FALSELY-PLIED STRAND AND AROUND SAID WRAPPED STRAND, SAIDWRAPPED STRAND AND SAID FALSELY-PLIED STRAND POSSESSING NO NET TRUETWIST AROUND ONE ANOTHER.
 4. THE METHOD OF PRODUCING A FALSELY-PLIEDYARN WHICH COMPRISES PASSING AT LEAST ONE WRAPPING STRAND AND AT LEASTONE CORE STRAND THROUGH A GENERALLY CYLINDRICAL BODY OF FLUID WHIRLINGABOUT A CENTRAL AXIS, THE WRAPPING STRAND BEING FED AT A RATE FASTERTHAN THE CORE STRAND, DISPOSING THE WRAPPING STRAND AROUND THE CORESTRAND IN THE FORM OF DOUBLED-BACK LOOPS WOUND FOR A MULTIPLICITY OFTURNS AROUND SAID CORE STRAND, A PORTION OF SAID LOOPS AT INTERVALSEXTENDING RADIALLY OUTWARD FROM THE AXIS OF SAID CORE STRAND; BRINGINGTHE THUS-FORMED WRAPPED YARN INTO JUSTAPOSITION WITH A SECOND STRAND,PASSING THE COMBINED YARN AND SECOND STRAND THROUGH A GENERALLYCYLINDRICAL BODY OF FLUID WHIRLING ABOUT A CENTRAL AXIS, WRAPPING ATLEAST SOME OF THE RADIALLY-DISPOSED LOOPS OF THE WRAPPED YARN AROUNDBOTH THE SECOND STRAND AND AROUND THE WRAPPED YARN, AND REMOVING THETHUS-FORMED FALSELY-PLIED FROM THE WHIRLING BODY OF FLUID.